The right to bear arms is famously and specifically referenced in the Second Amendment to the U.S. Constitution. Alas, for advocates of the right, the language of the amendment gets tangled up in the regulating of militias and the interpretation of commas. Now a multistate movement is trying to find more robust constitutional support in another amendment, which makes no mention of weaponry at all.

The 10th Amendment declares, "The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people." It inspired the so-called Sagebrush Rebellion that swept the West three decades ago, preventing the federal takeover of public lands pushed by the Carter Administration and propelling the self-proclaimed Sagebrush Rebel, Ronald Reagan, to the presidency. Now the Amendment is being invoked by pro-gun advocates to press for state, rather than federal, regulation of gun manufacturers.

Montana has passed a law allowing local gun manufacturers to sidestep federal regulations as long as the weapons they make are sold within the territory of the state. "It's a gun bill, but it's another way of demonstrating the sovereignty of the state of Montana," Democratic Governor Brian Schweitzer said, according to the AP, as he signed the bill into law in mid-April. "I like big guns, I like little guns, I like pistols, I like rifles, and I would like to buy a gun that's made in Montana."

In Texas (which recently saw Governor Rick Perry joking that the Lone Star State might take up the ultimate state right and secede from the Union), a similar bill is in committee as the legislative session winds down. Tennessee and Alaska "Firearms Freedom Acts" are working their way through the process. Utah may take up a bill next year.

The Montana law was drafted by the Montana Shooting Sports Association, which has said it will support what it is likely to be a lengthy legal fight in the federal court system to affirm or strike down the law. Plans call for the association to find a pristine individual who will manufacture and sell 20 rifles without applying for a mandatory federal dealer's license. The right to do so would be asserted in a letter to the Bureau of Alcohol, Tobacco and Firearms. Once a BATF response likely rejecting that claim is received, the association would seek standing in a Federal District Court to litigate its claim, experts say.

"It is part of the populist state-sovereignty movement, the sense there is so much power in Washington," says Stephen P. Halbrook, a Virginia attorney who has argued several important Second Amendment cases before the Supreme Court, including, most recently, a successful case overturning the Washington, D.C., gun ban. Halbrook says the Montana initiative had been simmering long before President Obama's election, which led to reports of a run on gun and ammunition across the country because of fear of new federal curtailment or taxation of gun ownership. "It is a grass-roots thing," Halbrook says, "not an NRA [National Rifle Association] initiative." The NRA, however, has expressed its support for the measure.

It is likely the Montana law will end up before the Supreme Court, Halbrook says, following the same track as the landmark Printz v. United States case, which he argued successfully before the court. That case was filed in Helena, Mont., challenging the constitutionality of requiring local enforcement officers to perform background checks required by the federal Brady Act, regulating handgun sales. The district court found the requirement unconstitutional but was overturned by the more liberal Ninth Circuit Court of Appeals in San Francisco. The lower court decision was affirmed by the Supreme Court in 1997, four years after the Brady Act passed. The ruling was, in effect, moot because a federal background database supplanted local background checks by the time the court ruled, but it left in place an important precedent on the limits of federal law — an issue that the new Montana law raises again.

Gun-regulation supporters say the Montana law is unconstitutional, citing long-standing court decisions going back to the Depression era based on the application of the so-called commerce clause regulating interstate commerce, the Wickard v. Filburn case, according to Paul Helmke, president of the Brady Campaign to Prevent Gun Violence. The courts have ruled that even if a farmer grows his wheat locally, sells it locally and someone buys it locally, the entire transaction process is still governed by interstate commerce because of the concept that his actions affect the entire marketplace — including, most importantly, the ability of a farmer in a neighboring state to sell his wheat across state lines.

"It is also bad politics," Helmke says. "I am asking, What are the federal rules they don't like? There are not that many federal laws on guns." The states' rights arguments echo the debates heard as far back as the 1830s. "That was settled with the Civil War," Helmke says. "They are part of the Union, and there are rules when you are part of the Union."

The irony is that most of the major gun manufacturers are located in blue states — Smith and Wesson in Massachusetts, Colt in Connecticut. Other large manufacturers, like Browning, located in Utah, are engaged in global commerce. Montana's bill will apply to boutique gun manufacturers who produce expensive custom-made hunting rifles, which are usually purchased by affluent hunters and collectors.

The Montana law will go into effect on Oct. 1, and the ensuing legal battle will be long, perhaps three years or more, Halbrook says. Helmke expects the Brady Campaign to join the fight. The Printz decision was a 5-4 split with the majority opinion written by Justice Antonin Scalia, but this latest challenge could be heard by a court sitting in Obama's second term or his successor's, meaning it will likely be a court with a different lineup.